Chicago Marathon
Race Day Weather
Cool start, shifting winds ahead
Runners will face a cool start at 57°F, rising to 61°F by the finish. Wind will be a factor with tailwinds in the early miles, shifting to headwinds from miles 2 to 13, which will challenge pacing efforts. With humidity at 71%, it's advisable to hydrate frequently and consider pacing conservatively, especially as conditions change throughout the race.
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Race Info
The Chicago Marathon starts and finishes in Grant Park, looping through 29 Chicago neighborhoods and crossing the Chicago River six times. The flat, fast course is a Boston qualifier and has produced seven marathon world records, most recently Ruth Chepng'etich's 2:09:56 women's mark in 2024. It's one of the seven Abbott World Marathon Majors, held every year on the second Sunday of October.
